Bluetooth: hci_ldisc: Remove dead code

The N_HCI ldisc does not define a flush_buffer() ldisc method, so
the check when opening the ldisc is always false.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c
index 03146d7..73202624 100644
--- a/drivers/bluetooth/hci_ldisc.c
+++ b/drivers/bluetooth/hci_ldisc.c
@@ -462,13 +462,7 @@
 	INIT_WORK(&hu->init_ready, hci_uart_init_work);
 	INIT_WORK(&hu->write_work, hci_uart_write_work);
 
-	/* Flush any pending characters in the driver and line discipline. */
-
-	/* FIXME: why is this needed. Note don't use ldisc_ref here as the
-	   open path is before the ldisc is referencable */
-
-	if (tty->ldisc->ops->flush_buffer)
-		tty->ldisc->ops->flush_buffer(tty);
+	/* Flush any pending characters in the driver */
 	tty_driver_flush_buffer(tty);
 
 	return 0;